US stocks tumbled in opening trade Monday, with the Dow plummeting more than 900 points as a global equity slump worsened following another big drop in Chinese stocks.

About three minutes into trade, the Dow Jones Industrial Average stood at 15,537.98, down 921.77 points (5.60 percent). The broad-based S&P 500 sank 91.65 (4.65 percent) to 1,879.24, while the tech-rich Nasdaq Composite Index fell 368.52 (7.83 percent) to 4,337.52.